Added AbpEntityFrameworkQueryableExtensions.IncludeIf

src/Volo.Abp.EntityFrameworkCore/Microsoft/EntityFrameworkCore/AbpEntityFrameworkQueryableExtensions.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Linq;
+using System.Linq.Expressions;
+
+namespace Microsoft.EntityFrameworkCore
+{
+    public static class AbpEntityFrameworkQueryableExtensions
+    {
+        /// <summary>
+        /// Specifies the related objects to include in the query results.
+        /// </summary>
+        /// <param name="source">The source <see cref="IQueryable{T}"/> on which to call Include.</param>
+        /// <param name="condition">A boolean value to determine to include <paramref name="path"/> or not.</param>
+        /// <param name="path">The type of navigation property being included.</param>
+        public static IQueryable<T> IncludeIf<T, TProperty>(this IQueryable<T> source, bool condition, Expression<Func<T, TProperty>> path)
+            where T : class
+        {
+            return condition
+                ? source.Include(path)
+                : source;
+        }
+    }
+}